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What do Clustered and Non clustered index actually mean?
I have a limited exposure to DB and have only used DB as an application programmer. I want to know about Clustered and Non clustered indexes .
I googled and what I found was :
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Does using “new” on a struct allocate it on the heap or stack?
...ut where value type variables are allocated. That's a different question - and one to which the answer isn't just "on the stack". It's more complicated than that (and made even more complicated by C# 2). I have an article on the topic and will expand on it if requested, but let's deal with just the ...
Comparing Dates in Oracle SQL
...C, doesn't necessarily mean December. It depends on your NLS_DATE_LANGUAGE and NLS_DATE_FORMAT settings. To ensure that your comparison with work in any locale you can use the datetime format model MM instead
The year '95 is inexact. You know you mean 1995, but what if it was '50, is that 1950 or 2...
What is stability in sorting algorithms and why is it important?
...ms are stable by nature like Insertion sort, Merge Sort, Bubble Sort, etc. And some sorting algorithms are not, like Heap Sort, Quick Sort, etc.
Background: a "stable" sorting algorithm keeps the items with the same sorting key in order. Suppose we have a list of 5-letter words:
peach
straw
appl...
Simple explanation of clojure protocols
I'm trying to understand clojure protocols and what problem they are supposed to solve. Does anyone have a clear explanation of the whats and whys of clojure protocols?
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Can I use an OR in regex without capturing what's enclosed?
I'm using rubular.com to build my regex, and their documentation describes the following:
4 Answers
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MySQL Error 1215: Cannot add foreign key constraint
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I'm guessing that Clients.Case_Number and/or Staff.Emp_ID are not exactly the same data type as Clients_has_Staff.Clients_Case_Number and Clients_has_Staff.Staff_Emp_ID.
Perhaps the columns in the parent tables are INT UNSIGNED?
They need to be exactly the same...
PHP and MySQL - how to avoid password in source code? [duplicate]
...configuration file.
Many frameworks use this (Zend, CakePHP, Kohana, etc) and it's the most common way of doing things (even in a non-PHP environment such as ASP.NET with its web.config files). This allows you also to copy over configuration values from environment to environment by just copying th...
Is there a REAL performance difference between INT and VARCHAR primary keys?
...AR as the primary key for reference lists (think US States, Country Codes) and a coworker won't budge on the INT AUTO_INCREMENT as a primary key for all tables.
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How to store arrays in MySQL?
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The proper way to do this is to use multiple tables and JOIN them in your queries.
For example:
CREATE TABLE person (
`id` INT NOT NULL PRIMARY KEY,
`name` VARCHAR(50)
);
CREATE TABLE fruits (
`fruit_name` VARCHAR(20) NOT NULL PRIMARY KEY,
`color` VARCHAR(20),
`price` INT
)...